NEW YORK, May 22 (Reuters) - Overstock.com unit t0.com (tZERO) said on Tuesday it has entered into a joint venture with BOX Digital Markets to launch a regulated exchange for security tokens.

The two firms entered into a letter of intent last week to create an exchange that will list and publicly trade security tokens, including those converted from a company’s existing stock. The proposed joint venture would be equally owned by tZERO and BOX Digital.

BOX Digital is a wholly-owned subsidiary of BOX Holdings Group LLC, which owns and operates BOX Market, an equity options marketplace and a facility of BOX Options Exchange.